Lawn-mower



(No Model.) I I Tv. JOHNSTON.

LAWN MOWER.

No. 566,911. Patented Sept. l, 1896.

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i el @Mmmm UNITED STATES PATENT 'Finca l THOMAS JOHNSTON, OF NEWBURG,NEW' YORK.

LAWN-MOWER.

SPECIFICATION forming part of Letters Patent No. 566,911, datedSeptember 1, 1896.

Application led August 16, 1895. Serial No. 559,530- (No modela To allwhom t may concern:

Be it known that I, THOMAS JOHNSTON, a citizen of the United States,residing at Newburg,in the county of Orange and State of New York, haveinvented certain new and useful Improvements in Lawn-Mowers; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled inthe art to whichit appertains to make and use the same.

This invention relates to an improvement vin lawn-mowers, and it isembodied in the construction hereinafter described and definitelyclaimed.

The invention consists in improved means for effecting the adjustment ofa cutting member of a lawn-mower.

The object of the invention is the provision of means for adjusting acutting member of a lawn-mower in a positive and easy manner and ineffecting such adjustment through the instrumentality of a cam oreccentric engaging or acting on the carrying frame or arms of thecutter, as distinguished from structures wherein the adjustment iseffected by direct adjustment of the cutter and screw adjustments.

A further object of the invention is to simplify the adjustment of acutting member and dispense with a plurality or multiplicity ofadjusting means.

The invention is illustrated in the accompanying drawings, wherein likeletters of reference designate corresponding parts in the several views,and in which- Figure l is an elevation of a side frame, showing thecutter and connecting-bars in section. Fig. 2 is a detail view of acarrying arm or frame, showing the adjusting device in section, with theange omitted. Fig. 3 is a longitudinal section of the arm and portion ofthe frame. Fig. et is a detail view of the eccentric. Fig. 5 is asection through the eccentric and its securing-bolt'or pivot-pin. Fig. 6is a detail perspective of the bolt or pin. Fig.

I have shown but one side of the machine, as the construction is thesaine on both sides.

B designates the carrying-arm which supports the revolving cutter. Thisarm is pivotally secured at its forward end to the side frame A by thebolt or pin b. The arm B has formed thereon at points rearwardly beyondits center the journal-boxes O, in which the supporting-shaft CZ of therevolving cutterreel D is journaled, the shaft extending through the armand the slot d, and receives its motion through the usual or any desireddrive connection with the ground Wheels. Between the box O and the pivotb is formed a curved guide-slot b2, through which passes a bolt b3,capped by a suitable head projecting over and laterally beyond the slot,and serves as a guide and brace for the arm. The rear end of the arm Bhas an oblong slot or recess E formed therein beyond the box O,extending longitudinally from points adjacent to the box and rear end.This slot has the curved end Walls e and the su bstantially straightside walls e. Vtithin this slot is placed a disk F, the curvature ofwhich corresponds with that of the ends of the slot. This disk ispivotally supported eccentrically by a pivotpin f, passing through thesame and frame A, the pin being located relative to the end walls of theslot at a point between the longitudinal center of the slot and forwardend wall. The pin has a conicalheadf and a threaded sectionf2, formedwith hat sides f3, which engage in a corresponding opening in the frameA, so that the same may be moved longitudinally, but is prevented fromrotating.

F' designates a binding-nuton the threaded end of the pivot-pin. Theeccentric has its outer face extended beyond the plane of the arm B andis formed with the flange f4 normally resting against the side ofthe'arm. Fz designates a squared lug on the outer face of the eccentric,having a central bore constituting a continuation of the disk-openingthrough which the pivot-pin passes. The bore of this lug is tapered atits outer end and forms a seat for the tapered section of the pin f.

Bythe above-described construction it will be seen that when it isdesired to adjust the cutting-reel or revolving cutterit is only nec'-essary to place a wrench on the squared lug F2 and turn the eccentric inthe slot, raising IOO or lowering the arm as desired. The elongation ofthe vslot permits themoveinent of the eccentric until the latter reachesits upward or downward limit, at which points the eccentric engages theforward wall of the slot and is prevented from moving farther'. Afterthe arm has been adjusted the nut F is tighten ed, drawing the pintightly into the tapered portion of the lug F2 and the iiange on theeccentric closely against the side of the arm, thus clamping the armsecurely in its adj usted position. The arm and cutter are, as will beseen, adjusted by the single instrumentality in either direction and arermly held in place after adjustment.

Heretofore it has been customary to use two or more adjusting-screws toeffect the adjustment, which is accomplished by tightening one screw andloosening the other. The advantage of the present form over the old formis obvious.

In Fig. 7 I have shown a modified form wherein the eccentric feature isapplied to the stationary cutter-bar. In this form the bar H is mountedon the arms 72 which are pivotally secured to the frame. The ends of thearms are recessed or formed with an elongated slot 7L', in which theeccentric Il is mounted. By turning the eccentric the arm is moved onits pivot from right to left, thereby adjusting the stationarycutter-blade relative to the revolving cutter-blades.

I am aware that many minor changes in the construction and arrangementof the parts can be made and substituted for those herein shown anddescribed without in the least departing from the nature and principleof my invention.

Having thus described the invention, what is claimed as new, and desiredto be secured by Letters Patent, is

1. In a lawn-mower, the combination with a frame, of arms pivotallysupported on the frame, and formed with elongated recesses therein, acutter carried by the arms, eccentrics located in the recesses, flan geson the eccentrics bearing against the arms, and means for securing theeccentrics in adjusted positions, substantially as described.

2. In a lawn-mower, the combination with the side frame, of a swingingarm pivotally secured thereto, having an elongated slot therein, acutter carried by the arm, an eccentrically-mounted adjuster located inthe slot, an angular projection on the adjuster, a pivot-pin passingthrough the same, and

means for securing the adjuster in its adjusted positions, substantiallyas described.

3. The combination with the pivotally-supported arm having an elongatedslot, of a cutter connected therewith, an adjuster consisting of a disklocated in the slot, a pin passing eccentrically through the disk, a lugon the disk having an angular exterior, a ange on the disk, and meansfor drawing the flange onto the arm, substantially as described.

In testimony whereof I affix myl signature in presence of two witnesses.

THOMAS JOHNSTON.

Witnesses:

LEWIS M. SMITH, CHAs. l-l. l-IALSTEAD.

